Cutting torch



April 23, 1929. E. H. SMITH ET AL CUTTING TORCH 5 Sheets-Sheet FiledSept. lO, 1927 In venors mm NW ELA/1ER H. SMITH HOME/L? E. 6A NNETTlllllllllllllll. 1/1111111 Aavorngs April 23, 1929 E. H. SMITH ET Al.

:CUTTING TORCH Filed Sept. l0, 1927 5 Sheets-Sheet In Ver: vors ELMER'H. 5M; TH HOME/'1 E. GANNETT E@ fm1 VWM April 23, 1929. E, H SMITH ET AL1,709,886

CUTTING TORCH Filed Sept. lO, 1927 5 Sheets-Sheet 5 58 3,7 AcETyLE/vE l.l l B I l l l l l l l I i i l I i n a i u l I l l um) (n M OO InventorsT T 1 G, ELMTHSM/Tf/ HOMER E. 6ANNETT Patented Apr'. 23, 1.929.

UNITED STATES PATENT 1,109,886 orifice.

ELMER II. SMITH, or MINNEAPOLIS, MINNESOTA, ANI)- Hoi/ian E. GANNETT, FBERWYN, ILLINOIS.

CUTTING Tonen.

' Application led September 10, 1927. Serial No. 218,825.

This invention relates tonew and useful improvements in cutting torches,generally;v and more particularly relates to such a torch having meansfor heating the metal directly under the cutting orifice so that theinitial cutting of the metal Will beexpedited.

Cutting torches, of ordinar construction, are usually provided With a purality of preheating orifices Which surround the central or cuttingorifice, through which the oxygen is projected against the metal forcutting. These outer orifices are connected With the fuel supply, and,when 'in operation, project a. plurality of heatlng' flames against themetal. The purpose of these flames 1s to heat the metal to a certaintemperature before the cutting operation can be started. The outer orpre-heating orifices are usually arranged on an angle so that the flamesconverge toward a point directly in alinement With the cutting orificeand comparatively close thereto. If the preheating orifices converge toomuch, the flames projected therefrom have a tendency to interfere Withthe operation of the cutting jet in that they tend to break up the solidjet of pure oxygen, required for the cutting operation, and W'ulnch isprojected from the central cutting orifice.

In order to obtain quick starting of the cutting operation, it is'necessary to bring the metal to a red heat very rapidly and in order todo this, the size of the preheating flames projected from the cuttingltip must necessarily be larger than is required to maintain the metalat the proper temperature during the cutting operation, after the'cutting is once started. It is, therefore, desirable that means beprovided whereby the initial heating of the metal may be expedited andWithout thenecessity of having to enlarge the preheating orifices, sothat when the cutting operation has been started, the preheating flamesprojected from the torch will be only sufficiently large to maintain themetal at the proper temperature for rapid cutting. In the method nowcommonly employed for cutting metal, the flames are projected againstthe metal until the latter is brought to a red heat. A jetof oxygen,usually cold, is then directed upon the heated spot Which sometimescools the metal to a point below the ignition point, after which itbecomes necessary to reheat the metal before cutting can be started.

The novel cutting torch featured in this invention is provided withmeans for quickly heating the metal to the required temperaturein acomparatively short time. This is accomplished by using the center or'cutting orifice as a preheating orifice. in addition to` the usualpreheating orifices arranged thereabout. To thus use the central orcutting orifice forprojecting a preheating flame against the Work, avalve mecha-- nism is provided upon the body of the torch for directinga portion of the fuel Agas and oxygen through this central orifice ofthe torch tip, simultaneously as the fuel gas and oxygen is projectedfrom the preheating orifices arranged thereabout. Thus, all oftheorifices in the torch tip may be used for projecting preheatingflames against the Work, before the cutting operation is started, re-

sulting in very rapid heating of the Work.

As soon as the metal has been heated to the proper temperature, thevalve mechanism is operated to gradually cut off the' supply ofacetylene or fuel gas to the central or cutting orifice, after Which thesupply of oxygen to the cutting orifice is increased. By thus graduallycutting off the fuel gas-and supplying additional oxygen to the cuttingorifice, the central flame gradually changes neutral to lan oxidizingflame, and

from a thence to a jet of pure oxygen, and, finally as the oxygenpredominates to such an extent that combustion Will barely continue, thecutting operation commences. By thus controlling, first, the fiowofjacetylene or fuel gas to the central cutting orifice and thenincreasing the supply of oxygen therej to, the flame projected from thecentral orifice Will, as above stated, first, be a neutral or preheatingfiame, will then change to an oxidizing flame, comprised mainly ofoxygen heated to a high degree, and finally to a jet of pure oxy en forcutting, thereby greatly expediting the initial heating lof the metalpreparatory to the cutting operation. l An object of the inventiontherefore is to provide an improved cutting torch comprising a valvemechanism forcontrolling the flow of'fuel gas and oxygen through thetorch tip, and, whereby fuel gas and oxygen may be directed through thecentral or cutting orifice to assist ,in initially heating the metalbefore cutting is started, said valve mechanism being so constructed andarranged that a standard torch tip may be used'.

Other objects of the invention reside 'in the constructional details ofthe valve mechanism; the means provided for cutting off the supply offuel gas to the central orifice and supplying additional oxygen thereto;in the provision of a mixing chamber in the head ofthe torch; and, inthe simplicity of the torch and in the convenience with out the variousobjects of the invention, butwhich it may be operated.

Other objects of the invention will appear from the followingdescription and accompanying drawings and will be .pointed out .in theannexed claims.

In the accompanying drawings, there has been disclosed a structuredesigned to `carry it isl to be understoody that the invention is notconfined to the exact' features shown as various changes may be madewithin the scope of the claims which follow. c

In the accompanying drawings forming part of this specification;

Figure 1 is a sectional view on the line ,1--1 of Figure 2, showing thegeneral conthe construction thereof;

Figure 7 is a view showing the tip removed from the torch head; 0

Figure 8 is a view showing the discharge end of the torch tip; and

Figure 9 is a diagrammatic view showing the connections between thevarious valves and the torch ti A In the selected embodiment of theinvention here shown', for the purposes of disclosure, there isillustrated a cuttmg torchcomprising a head 2 having threaded vsockets 3and 4 to which are secured respectively pipes 5, and 6. The oppositeends of the pipes 5 and 6 are secured to a valve body 7 having threadedextensions 8 and 9 for connecting the torch to a supply of' oxygen andacetylene, as indicated in Figures 1 and 9.

The torch head 2 has provided in the lower end thereof,ya threadedsocket11 ladaptf ed to receive the threaded -portion 12 of a torch tip 13. Thetorch tip is secured to the head by means of a packing nut 14 receivedin threaded engagement. with the extension 15 of the head. A packinggland 16 cooperates'with the nut 14 to provide a j leak-proof jointbetween the' exterior of thetorch tipfand the'threaded extension 15ofthe head.

The torch tip'13 is provided with the usual pre-heating orifices 17 andthe central cutting or oxygen orifice 18, as shown in Figures 1 and 9.`The preheating orifices 17 are preferably arranged around the centralcutting orifice 18 as shown' in Figure 8. A plurality of radial ducts 19are provided in the upper portion of the tip 13, and connect theorifices 17 with an annular chamber 21, provided in the lower portion ofthe extension 15. duct 22 is provided in the lower portion of the ,head2 and connects the annular chamber 21 with the interior of the pipe 6.Tubes 23 and 24 are mounted respectively within the pipes 5 and 6 asshown in Figure 1. These tubes each have on end secured in the torchhead 2 and their opposite ends connected with the valve body 7. One endof the tube 24 is connected by a duct 25 to an annular chamber 26,provided around the reduced end portion 27 of the torch tip. Thisannular chamber 26 is in direct communication with'the upper ends of thepreheating orifices 17, provided in the tip 13 as shown. The other endof the tube U24 is connected by a duct 28 to a small valve chamber 29,having a valve seat 31 in the lower portion thereof adapted to beengaged by a valve stem 32.. A port 33 connects the valve. chamber 29with a supply conduit'34, terminating in the threaded extension 8 of thevalve body. (See Figuresv (See Figures l and 9.) A

1 and 9.) The opposite end of the conduit 34 leads to a control valve35, the operation of which will be subsequently described.

The pipe 6, in which the tube 24 is mount- A ed, has a port 36connecting it .with a valve chamber 37, provided in a valve body 7. Thisvalve chamber has a similar valve seat `38 adapted to be engaged by avalve stem 39, to control the fiow of fluid therethrough. The valvechamber 37 is connected by a port 41 to a supply conduit 42, having oneend terminating in the threaded extension 9, as 'shown in Figures` 1 and9. The opposite end of the conduit 42 terminates in a valve chamber. 43having va valve stem 44 A provided therein for controlling the flow offluid therethrough. This valve chamber is connected by a conduit 45, to'a control valve 46 mounted adjacent to the control valve 35, as shownin Figures 2 and 9. The operation of this valve will subsequentlybedescribed.

A port 47 is centrally provided in the torch head 2 and has one endcommunicat- `'ing with the central orifice 18, in the torch tip,l andits other end communicating with a cone-shaped mixing chamber 48. Thismixing chamber is defined by the cone-shaped bottomof a threaded socket49 provided 'in the head, and by the tapered point of a p lug 51,received in threaded engagement with the socket 49 asshown' in Figure 1.The mixing chamber 48 is connected by a passage52 to one end of the pipe5. An orifice 53 is provided in the plug 51 which is connected by a duct54 to the adjacent end of the tube 23, as shown particularly in Figure1.- The opposite end of the pipe 23 is connected with a valve chamber55'by means of a duct 56, provided in the valve body 7. The valvechamber 55 is connected by a duct 57 t the supply conduit 34, and a.needle valve 58 is mounted within he chamber 55 toI control the flow ofHuid therethrough. A by-pass 59 connects the valve 35 with the tube 23,as 'shown in Figure 9.

When the two oxygen valves 32 and 58 and also the two acetylene valves39 and -44 are in the partially open positions shown in Figure 9,acetylene and oxygen will be supplied to the orifices 17 and 18 providedin the torch tip, with the result that a plurality of preheating flameswill be projected therefrom to preheat the metal preparatory to cutting.The construction of these valves and their connections with the torchtip and fuel supplies, are such that they need not be regulated oradjusted after once having been set to supply the proper quantity ofoxygen and acetylene to the torch tip for the preheating operation.Shut-off valves, not s own, are usually provided between the connections8 and 9 and the source of supply vfor cutting off the fluid supply, whenthe cutting torch is inoperative.

When the needle valves have been adjusted to the positions shown inFigure' 9, wherein both oxygen and acetylene will be supplied to theorifices 17 and 18, in the torch tip, it will be seen that before thecutting operation can be started, the supply of acetylene to the centralcutting orifice must be cut off and the supply of oxygen thereto must beincreased. This is accom.- plished by means of the valves 35 and 46,hereinbefore mentioned. These valves are mounted respectively in bores61 and 62, provided in cylindrical extensions 63 and 64, provided uponthe valve body 7, as shown in Figure 2. The valve 35 is provided with `astem 65 passing`thro1gh a stuffing b'ox 66,

and the valve 46 is similarly provided with a stem 67, having one endpassing through a similar stuiiing boX 68. The valve stem 65 has abracket 69 terminally secured thereto having a slot 71 adapted toreceive an ex'- tension 72, provided upon a lever 73 having a fingergrip 74 thereon, whereby it may be conveniently operated. The stem 67Vof the valve 46 likewise has a bracket 75 terminally secured theretowhich also has a slot 76 adapted to receive the end portion 77 of anoff-set extension 78, also provided upon the lever 73. The lever 73 issupported upon a pivot 79 secured to a bracket 81 suitably clamped orsecured to the pipe 6 by such means as al set screw 82, shown in Figures1 and 2. The finger grip 74 is slidably secured to the lever 73 and hasa notch 83 provided therein which isadapted to engage the end of aslot`84 provided in a casing 85 which surrounds the major portions ofthe pipes 5 and 6 and, through which the plate-like portion 86 of thefinger grip projects. (See Figure 1.) A tension spring has one endattached lto the extension 77 and its other end to the end wall 80 ofthe casing 85 and functions to retain the lever 73 in its normal 1 and9.

Figures 1, 2, and 9 illustrate the position of the lever 73 and thevalves 35 and 46, when the torch is used in the initial operation ofpreheating the work, prior to starting the cutting operation. Thistherefore,

1s the normal position of the parts. A -spring 87 is coiled labout thevalve stem 65 and normally holds the valve 35 in its closed position, asshown in Figure 2. A lrelatively smaller spring 88 is also coiled yaboutthe valve stemA 67 and constantly tends to urge the valve 46 intoclosing position against the tension of the relatively strongerv spring87. The slots 71 and 76 provided respectively in the brackets 69 and 75are relatively longer than the widths, of the extensions 72 and 77 sothat when the linger grip 74 is depressed, the valve 46 will be movedinto closing position before the valve 35 begins to open. Conversely,when the valve 35 is moved into closing position, the valve 46 will notbe lifted from its seat until the valve 35 has been moved into closingposition'.

In Figure 9, the lever73 and the valves 35 and 46A are shown in theirnormal posiposition, shown in Figures tions such as when the torch isused for preheating the Work. By reference to this figure, it will benoted that the valve 35 is in closed position and that the extension 72of the lever 73 does not engage either end of the slot 71. The valve'46, however, is open, caused by the extension 77 engaging one end ofthe slot 76, as a result of the spring 70 holding the lever 73 in itsnormal position. The strength of the spring 70, therefore, is greaterthan -that of the spring 88, so that it will hold the parts in theposition shown in Figure 9, against the tension of the spring 88. Bythus arranging the valves with their complementary springs, it will beseen that when the lever 73 is depressed'to the position shown in Figure6, the spring 88 will cause the valve 46 to be moved into closingposition, before the extension 72 engages the outer end of the slot 71and opens the valves 35. Such actuation of the valves. 35 and 46 afterwhich,when oxygen and acetylene is Cil V 74'is depressed or moved intothe position` supplied respectively to the conduits 34 and 42, acombustible fuel mixture will be discharged from the orifices 17 and18provided in the torch tip. This fuel mixture, when ignited, providesan intense heating flame which, `when directed against the work, willquickly heat it to the desired temperature for cutting,` As soon as themetal has been heated to such temperature, the finger grip shown inFigure 6, thereby closing the valve 46 and cutting off the supply offuel gas tothe central orf cutting orifice 18 and, subsequently openingthe valve to allow additional oxygen to flow through the by-pass 59 andinto the tube 23, to increase the supply of oxygen to the cuttingorifice18, thereby starting the cutting operation. vBy thus controllingthe flow of'acetylene and oxygen through the central orifice 18 ofthetorch tip, the flame projected from the central or cutting orifice 18can be gradually changed from a neutral or heating flame to a highlyoxidizing-flame, and the-n to a'jet of-pure oxygen, which will beprojected or impinged against the highly heated metal surface, with theresult that cutting immediately starts. This is accomplished as a resultof using the central cutting orifice 18 in addition to the preheatingorifices 17 arranged thereabout,

` for initially heating the work. It has also been found that by usingthe central or oxygen orifice 18 as a preheating orifice, before thecutting operation is started, that the supply of fuel gas or mixturedischarged from the'preheating orifices 17 may be materially decreasedbecause of the fact that after actual cutting is started, less heat isrequired than4 in starting.

. We claim as our invention:

1. A cutting torch comprising a head having an orifice therein, meansfor supplying a cutting gas to said orifice, a conduit for supplying rafuel gas thereto, valves for controlling said gases, anda control leveroperatively' connecting said valves and adapted to simultaneouslyoperate said valves to cut off the supply of fuel gas from s'aid orificeand increasing the iiow of cutting gas thereto, whereby the flame isconverted from a heating to a cutting' flame.

2. A cutting torch comprising a head having a duct therein, a mixingchamber also in said head, a conduit for supplying fuel gas to saidchamber, a valve in said conduit, a second conduit for supplying oxygento said chamber and also having a valve therein,

' and means for simultaneously operating said valves to cut off thesupply of fuel gas to said chamber and to increase the'supply of oxygenthereto, whereby the cutting operation is started.

jected therefrom to assist in initially heating'- d the work and toexpedite the heating operation, and means operable to cut off the fuelsupply to said duct and deliver a cutting fluid thereto to start thecutting operation.

4. A cutting torch comprising a head having a preheating orifice thereinconnected with a fuel supply and from which a flame may be projected topreheat the work prior to'cutting, a duct also in saidfhead adjacent tosaid orifice and having means for connecting it with said fuel Supplyand also with a source of oxygen, whereby a preheating fiame may also beprojected therefrom to assist in initially heatinglithe work and to.expedite the heating operation, andv a valve mechanism operable togradually cut off the fuel supply from said duct andto increase thesupply of oxygen thereto, whereby the cutting operation is accelerated.

' 5. A. cutting torch comprising a head having a plurality of preheatingorifices therein Vconnected with the source of fuel supply and fromwhich fiames may be projectedto pre heat the work prior to cutting, aduct also in said head having means for connecting it with said fuelsupply, whereby a preheating flame may also be projected therefromv toassist 1n initially heatingthe work and i to expedite the heatingoperation, a valve connected with said duct and having a connection witha source of cutting fluid, a second valvefor controlling the supply offuel to said duct, and means for simultaneously operating said valves toout off the supply of fuel to said duct and to deliver a cutting fluidthereto whereby the cutting operation is started.

6. A cutting torch comprising a head having a plurality of preheatingorifices therein connected with a fuel supply, a cutting jet duct alsoin said heada conduit connecting said duct with a source of fuel gas, atubular' member connecting said duct with a source of oxygen, valves forcontrolling the normal supply of fuel gas and oxygen to said conduit andsaid tubular member, a' pair of plunger valves associated with saidconduit and said tubular member, and means for operating said plungervalves to cut off the supply offuel gas to said cutting jet duct and toincrease the flow o f oxygen thereto to provide a cuttin jet.

Y 7. A cutting torc comprising a head having a plurality of preheatingorifices therein connected with a source of fuel supply, a

cutting jet duct also in said head, means for supplying fuel gas andoxygen to said duct whereby a preheating flame may be projectedtherefromto assist in preheating the Work, a by-pass associated with said ductand With a supply of oxygen, and a valve mechanism operable to cut offthe supply of fuel gas to said duet and to open sa1d by-pass to increasethe supply of oxygen to said duct, whereby a cutting jet may beprojected therefrom.

8. A cutting torch comprising a head having a cutting jet duct therein,a mixing ihamber at one end of said duct, a pipe hav- ,ing one endconnected With said mixing chamber and its other end connected With asource of fuel gas, a tubular member mounted within said pipe and havingone end connected With said ymixing chamber and having its other endconnected with a source of oxygen, valves for controlling the normalsupply of fuel gas and oxygen respectively to said pipe and said tubularmember, a normally closed plunger valve connected with said oxygensupply,l a by-pass connecting said valve With said tubular member, asecond Valve interposed in the connection between said pipe and thesource of fuel gas and normally open, a lever for operating said valves,said lever being adapted to close said `second valve to cut off thesupply of fuel gas to said mixing chamber, and thereafter to open saidplunger valve to permit the flow of oxygen through said by-pass, wherebyan increased flow of pure oxygen is delivered to said cutting duct toprovide a cutting jet. In Witness whereof, We have hereunto set ourhands thisfth day of September 1927.

ELMER H. SMITH. HOMER E. GANN ETT.

